Terraform Version Detector in GitHub Actions

Automatic detection of Terraform version for hashicorp/setup-terraform action step.

Detects the version from (in order of priority):

1. required_version constraint in terraform {} blocks in .tf files
2. .terraform-version file (used by tfenv/tfswitch)
3. fallback-version input, or latest release if not specified

Basic usage:

steps:
- uses: actions/checkout@v5

- uses: skokado/terraform-version-detector@v1.2
  id: terraform-version
  with:
    path: path/to/dir

- uses: hashicorp/setup-terraform@v3
  with:
    terraform_version: ${{ steps.terraform-version.outputs.terraform-version }}

Examples

steps:
- uses: actions/checkout@v5

# --- app1/terraform.tf
# terraform {
#   required_version = ">= 1.10.0, < 1.11.0"
# }
- uses: skokado/terraform-version-detector@v1.2
  id: sample1
  with:
    path: app1/

- run: echo ${{ steps.sample1.outputs.terraform-version }}
# => Latest of 1.10.x 

Using a fallback version with detection check:

steps:
- uses: actions/checkout@v5

- uses: skokado/terraform-version-detector@v1.2
  id: terraform-version
  with:
    path: path/to/dir
    fallback-version: "1.10.5"

- if: steps.terraform-version.outputs.version-was-detected == 'false'
  run: echo "Warning - no Terraform version pinned, using fallback"

- uses: hashicorp/setup-terraform@v3
  with:
    terraform_version: ${{ steps.terraform-version.outputs.terraform-version }}

For more details, see Terraform documentation on Version Constraints.

Inputs

Input	Description	Default
path	Path to the directory containing Terraform configuration files.	.
fallback-version	Version to use when no version constraint is found.	latest

Outputs

Output	Description
terraform-version	The detected Terraform version based on the required_version constraint, .terraform-version file, or fallback.
version-was-detected	true if a version was found in the Terraform configuration, false if the fallback/latest was used.